Reversible monkey wrench

Abstract

A reversible monkey wrench includes a handle, a head, a slidable jaw, an axial rod and a worm gear. The handle has a connecting end for the head to abut thereagainst. The head is formed with a fixed jaw, a sliding rail, a receiving slot and a connecting bore. The connecting bore communicates with the receiving slot. A movable pin and a spring are disposed between the connecting end and the head. A top of the movable pin selectively inserts through the connecting bore. The spring urges the movable pin so that the movable pin may abut against the connecting end. The worm gear is adapted to control the slidable jaw to move and is slidably disposed in the receiving slot with respect to the axial rod. The movable pin selectively abuts against the worm gear to prohibit the worm gear from sliding.

What is claimed is: 
     
       1. A reversible monkey wrench, comprising:
 a handle, having a connecting end; 
 a head, being formed with a fixed jaw, a sliding rail, a receiving slot and a connecting bore, the sliding rail having a slide surface disposed at its top, the receiving slot communicating with the sliding rail, the connecting bore communicating the receiving slot with a bottom of the head; a joint axle, a first spring, a movable pin and a second spring being disposed between the head and the connecting end, the joint axle being located between the first spring and the movable pin, the head being rotatable with respect to the handle and about the joint axle, the first spring abutting against the head and the connecting end, a top of the movable pin selectively inserting through the connecting bore, the second spring being adapted to urge a bottom of the movable pin to abut against the connecting end, the first spring providing an elastic force bigger than an elastic force provided by the second spring; 
 a slidable jaw, having a sliding rod, the sliding rod being slidably disposed in the sliding rail; 
 an axial rod, stationarily disposed in the receiving slot; 
 a worm gear, having an engaging portion corresponding to the sliding rod, and having an axial bore for the axial rod to insert therethrough, the worm gear being disposed in the receiving slot and being slidable along the axial rod, the movable pin selectively abutting against an abutting end of the worm gear so as to prohibit the worm gear from sliding along the axial rod. 
 
     
     
       2. The reversible monkey wrench of  claim 1 , wherein the axial bore includes a wide section bore and a narrow section bore, the wide section bore is formed from the abutting end of the worm gear, a joint of the wide section bore and the narrow section bore is formed with a shoulder portion, the axial rod includes a thicker section rod and a thinner section rod, the thicker section rod inserts into the wide section bore from the abutting end, the thinner section rod inserts through the narrow section bore, an annular space is defined between the thinner section rod and the wide section bore, a third spring is disposed in the annular space, the third spring abuts against the thicker section rod and the shoulder portion and is hidden in the worm gear. 
     
     
       3. The reversible monkey wrench of  claim 2 , wherein the reversible monkey wrench is adapted to drive a hexagonal nut, a length between two opposite angles of the hexagonal nut is e, a length between two opposite sides of the hexagonal nut is s, the worm gear further has a smooth portion locating between the abutting end and the engaging portion, a diameter of the smooth portion is no bigger than a root diameter of the engaging portion, a length of the smooth portion is no smaller than (e−s). 
     
     
       4. The reversible monkey wrench of  claim 2 , wherein the movable pin has an abutting rim radially extending therefrom, the second spring surrounds the movable pin and abuts against the abutting rim and the head. 
     
     
       5. The reversible monkey wrench of  claim 1 , wherein the reversible monkey wrench is adapted to drive a hexagonal nut, a length between two opposite angles of the hexagonal nut is e, a length between two opposite sides of the hexagonal nut is s, the worm gear further has a smooth portion locating between the abutting end and the engaging portion, a diameter of the smooth portion is no bigger than a root diameter of the engaging portion, a length of the smooth portion is no smaller than (e−s). 
     
     
       6. The reversible monkey wrench of  claim 5 , wherein the movable pin has an abutting rim radially extending therefrom, the second spring surrounds the movable pin and abuts against the abutting rim and the head. 
     
     
       7. The reversible monkey wrench of  claim 5 , wherein a diameter of the movable pin is no smaller than (e−s). 
     
     
       8. The reversible monkey wrench of  claim 1 , wherein the movable pin has an abutting rim radially extending therefrom, the second spring surrounds the movable pin and abuts against the abutting rim and the head. 
     
     
       9. The reversible monkey wrench of  claim 1 , wherein the connecting end is formed with a protrusive spherical surface for the bottom of the movable pin to abut thereagainst. 
     
     
       10. The reversible monkey wrench of  claim 1 , wherein the bottom of the movable pin is formed with a protrusive spherical surface for the connecting end to abut thereagainst. 
     
     
       11. The reversible monkey wrench of  claim 1 , wherein the movable pin has a plane surface axially extending from the top of the movable pin, the plane surface abuts against with the abutting end of the worm gear. 
     
     
       12. The reversible monkey wrench of  claim 1 , further comprising a rotation-free means for prohibiting the movable pin from rotating about an axis of the connecting bore. 
     
     
       13. The reversible monkey wrench of  claim 1 , wherein the head further has a pair of wings parallelly extending from the bottom of the head, a departing slot is formed between the wings to receive the connecting end therein. 
     
     
       14. The reversible monkey wrench of  claim 13 , further comprising a locking device, the locking device comprising an elongated slot, an L-shaped slot and a controlling pin, the elongated slot being disposed either on at least one of the wings or on the connecting end, the L-shaped slot being disposed either on at least one of the wings or on the connecting end where the elongated slot is not disposed, the controlling pin inserting through the elongated slot and the L-shaped slot, and the controlling pin being movable between both ends of the elongated slot, whereby adjusting the head to be rotatable or nonrotatable with respect to the handle.